Method of fabricating organic light emitting display and display fabricated by the method

Abstract

The present invention provides a method of fabricating an improved organic light emitting display (OLED) as well as an OLED fabricated by the method. The method may include the following steps, which may be performed in any suitable order. At a first step, a substrate having at least one cell region is provided. At a second step, a light emitting device portion having at least one light emitting device is formed on the cell region. At a third step, a passivation layer is formed on the light emitting device portion. At a fourth step, a thin film transistor (TFT) portion is formed on the passivation layer. The TFT portion has an organic TFT (OTFT) electrically connected to each of the light emitting devices.

1 . A method of fabricating an organic light emitting display comprising: 
 providing a substrate having at least one cell region;    forming a light emitting device portion on the cell region, the light emitting device portion having at least one light emitting device;    forming a passivation layer on the light emitting device portion; and    forming a thin film transistor portion on the passivation layer, the thin film transistor portion having an organic thin film transistor electrically connected to each of the light emitting devices.    
     
     
         2 . The method of  claim 1 , wherein forming the passivation layer comprises forming the passivation layer on a side portion of the light emitting device portion.  
     
     
         3 . The method of  claim 1 , wherein forming the passivation layer comprises forming the passivation layer on a side surface of the substrate.  
     
     
         4 . The method of  claim 1 , wherein forming the passivation layer comprises forming the passivation layer on a bottom surface of the substrate.  
     
     
         5 . The method of  claim 1 , wherein the passivation layer is selected from a group consisting of an organic passivation layer, an inorganic passivation layer, and a double layer thereof.  
     
     
         6 . The method of  claim 5 , wherein the organic passivation layer is a parylene layer.  
     
     
         7 . The method of  claim 6 , wherein the parylene layer is formed by a chemical vapor deposition method.  
     
     
         8 . The method of  claim 1 , wherein the passivation layer is formed to a thickness of about 1000 Å to about 1 μm.  
     
     
         9 . The method of  claim 1 , wherein forming the light emitting device comprises: 
 forming a lower electrode on the cell region;    forming an organic layer having an emission layer on the lower electrode; and    forming an upper electrode on the organic layer.    
     
     
         10 . The method of  claim 9 , wherein the upper electrode is formed as one of an anode and a cathode.  
     
     
         11 . The method of  claim 9 , wherein the upper electrode is one of a reflective electrode and a double layer of a transparent electrode and a reflective layer.  
     
     
         12 . The method of  claim 1 , wherein forming the organic thin film transistor comprises: 
 forming a source electrode and a drain electrode on the passivation layer to be spaced apart from each other;    forming an organic semiconductor layer between the source electrode and the drain electrode to be connected to the source electrode and the drain electrode;    forming a gate insulating layer on the organic semiconductor layer; and    forming a gate electrode on the gate insulating layer.    
     
     
         13 . The method of  claim 12 , further comprising, before the formation of the organic thin film transistor, forming a contact hole in the passivation layer to expose the light emitting device, 
 wherein the drain electrode is electrically connected to the light emitting device through the contact hole.    
     
     
         14 . The method of  claim 12 , wherein the organic semiconductor layer is formed of a material selected from a group consisting of pentacene, tetracene, rubrene, α-hexathienylene, poly(3-hexylthiophene-2, 5-diyl), poly(thienylene vinylene), C60, NTCDA, PTCDA, and F16CuPc.  
     
     
         15 . The method of  claim 1 , wherein the organic thin film transistor is one of a PMOS transistor and an NMOS transistor.  
     
     
         16 . The method of  claim 1 , wherein the substrate is one selected from a group consisting of a glass substrate, a quartz substrate, and a plastic substrate.  
     
     
         17 . An organic light emitting display, comprising: 
 a substrate;    a light emitting device portion disposed on the substrate and having at least one light emitting device;    a passivation layer disposed on the light emitting device portion; and    a thin film transistor portion disposed on the passivation layer and having an organic thin film transistor electrically connected to each of the light emitting devices.    
     
     
         18 . The display of  claim 17 , wherein the passivation layer is disposed on a side portion of the light emitting device portion.  
     
     
         19 . The display of  claim 17 , wherein the passivation layer is disposed on a side surface of the substrate.  
     
     
         20 . The display of  claim 17 , wherein the passivation layer is disposed on a bottom surface of the substrate.  
     
     
         21 . The display of  claim 17 , wherein the passivation layer is one selected from a group consisting of an organic passivation layer, an inorganic passivation layer, and a double layer thereof.  
     
     
         22 . The display of  claim 21 , wherein the organic passivation layer is a parylene layer.  
     
     
         23 . The display of  claim 17 , wherein the passivation layer has a thickness of about 1000 Å to about 1 μm.  
     
     
         24 . The display of  claim 17 , wherein the light emitting device comprises: 
 a lower electrode disposed on the substrate;    an upper electrode disposed on the lower electrode; and    an organic layer interposed between the upper electrode and the lower electrode and having an emission layer.    
     
     
         25 . The display of  claim 24 , wherein the upper electrode is one of an anode and a cathode.  
     
     
         26 . The display of  claim 24 , wherein the upper electrode is one of a reflective electrode and a double layer of a transparent electrode and a reflective layer.  
     
     
         27 . The display of  claim 17 , wherein the organic thin film transistor comprises: 
 a source electrode and a drain electrode disposed on the passivation layer and spaced apart from each other;    an organic semiconductor layer interposed between the source electrode and the drain electrode and electrically connected to the source electrode and the drain electrode;    a gate insulating layer disposed on the organic semiconductor layer; and    a gate electrode disposed on the gate insulating layer and overlapping the organic semiconductor layer.    
     
     
         28 . The display of  claim 27 , wherein the drain electrode is electrically connected to the light emitting device by penetrating the passivation layer.  
     
     
         29 . The display of  claim 27 , wherein the organic semiconductor layer is formed of a material selected from a group consisting of pentacene, tetracene, rubrene, α-hexathienylene, poly(3-hexylthiophene-2, 5-diyl), poly(thienylene vinylene), C60, NTCDA, PTCDA, and F16CuPc.  
     
     
         30 . The display of  claim 17 , wherein the organic thin film transistor is one of a PMOS transistor and an NMOS transistor.  
     
     
         31 . The display of  claim 17 , wherein the substrate is one selected from a group consisting of a glass substrate, a quartz substrate, and a plastic substrate.